Covered container with removable tear strip



COVERED CONTAINER WITH REMOVABLE TEAR STRIP Filed June 11, 1962 J. A.FOSTER Oct. 12, 1965 4 Sheets-Sheet 1 I MVEJM-Vc Q hm QA.%JZ%7J J. A.FOSTER 3,211,323

COVERED CONTAINER WITH REMOVABLE TEAR STRIP Oct. 12, 1965 4 Sheets-Sheet2 Filed June 11, 1962 K, ef'

Qjch g Oct. 12, 1965 J. A. FOSTER 3,211,323

COVERED CONTAINER WITH REMOVABLE TEAR STRIP Filed June 11, 1962 4Sheets-Sheet 3 M 60km Cfi. h gJt-gT/ 1 wwwmw Oct. 12,1965 J. A. FOSTER3,211,323

COVERED CONTAINER WITH REMOVABLE TEAR STRIP Filed June 11, 1962 4Sheets-Sheet 4 TTQRIOEVJ United States Patent Manufacturing (10.,Rockford, Ill., a corporation of Illinois Filed June 11, 1962, Ser. No.201,431 6 Claims. (Cl. 22054) This invention relates to a container ofthe type in which a tubular body having an external bead around the lipat its open end is closed by a cover having a gasket and a dependingperipheral skirt bent around and interlocked with the bead to compressthe gasket and seal the cover against the lip, the skirt being weakenedalong a score line intermediate its edges so that the lower portion ofthe skirt may be torn away to release the cover from the body.

The general object is to provide a tear strip container of the abovecharacter which, after tearing of the skirt and initial removal of thecover, is adapted for reclosure and effective rescaling automatically asan incident to replacing the torn cover on the container body.

A more detailed object is to provide a cover of resilient material andlocate the score line on the skirt in a novel relation with respect tothe maximum diameter of the body engaged thereby so that the resiliencyof the torn skirt may be utilized to achieve a snap-like reclosing ofthe container.

A further object is to vary the thickness of the score line of the skirtin a novel manner for facilitating removal of the cover when the sealedcontainer is under a substantial internal vacuum.

The invention also resides in the novel shaping of the body bead and thecover skirt to achieve the foregoing objects.

Other objects and advantages of the invention will become apparent fromthe following detailed description taken in connection with theaccompanying drawings, in which FIGURE 1 is a perspective view of theimproved container with the tear strip partially removed.

FIG. 2 is an exploded elevational view.

FIG. 3 is an enlarged fragmentary sect-ion taken along the line 33 ofFIG. 2.

FIGS. 4, 5 and 6 are fragmentary diametrical sections showing successivesteps in the assembly of the cover on the container body, FIG. 6 beingtaken along the line 6-6 of FIG. 1.

FIG. 7 is a view similar to FIG. 6 after removal of part of the tearstrip.

FIG. 8 is a view similar to FIG. 7 after removal of the cover followingremoval of the tear strip.

FIG. 9 is a view similar to FIG. 8 but on a somewhat larger scale afterreplacement of the cover on the cup.

FIGS. 10 and 11 are tracings of actual fragmentary sections enlargedtwenty times and taken respectively along the lines 1010 and 1111 ofFIG. 1.

FIG. 12 is a perspective view of the container after removal of half ofthe tear strip.

FIGS. 13 and 14 are enlarged sections similar to FIG. 10 taken along theline 1313 of FIG. 11 and illustrating different directions of pulling ofthe tear strip.

In the drawings, the invention is shown for purposes of illustrationincorporated in a container comprising a tubular body or cup 10 closedat its bottom and open at its upper end which is defined by a lip havinga rounded axially facing surface 11 abutting a gasket 12 which issecured to the underside of a generally flat cover 13 and compressedagainst the lip as shown in FIGS. 6 and 10 to provide a seal capable ofwithstanding a substantial pressure differential. While the cup may bemade from 3,211,323 Patented Oct. 12, 1965 various materials, it ispreferably composed of semiresilient sheet metal such as an alloy ofaluminum known as Alcoa 3003-H14 about .009 of an inch thick.

The cover is preferably composed of the same material and comprises aflat top 14 depressed within a peripheral bead 15 which opens downwardlyto provide a downwardly opening groove 15 partially filled to a depth ofabout .050 of an inch by the gasket 12. The latter is formed bydelivering into the groove with the cover inverted an accuratelymeasured volume of a creamy liquid which is solidified by heat to leavethe exposed surface 12 substantially fiat and perpendicular to the coveraxis. The gasket is relatively soft and resilient so as to possess thedesired compressibility under the available pressure while providingbetween the cover and the body lip 11 a seal which will remain airtightfor a substantial period of time. For this purpose, a polyvinyl chlorideso-called puff compound sold by Dewey and Almy may be employed. Byheating to about 400 degrees, this material is converted into a ring offine foam as shown in FIG. 4.

Compression of the gasket is achieved by telescoping a skirt 17depending from the outer edge of the cover down over a bead 18 ofrounded cross-section formed around the cup lip and providing adownwardly facing shoulder or ledge 19 with which the lower edge portionof the skirt is interlocked in the final assembly (FIGS. 1, 6 and 10) toretain the compressed condition of the gasket. After blanking a sheetand drawing a generally cylindrical cup, the metal at the open end issubjected to conventional flanging and heading operations to curl theedge portion of the cup into the form shown in FIG. 3. From the arcuateupwardly facing lip surface 11, the outer surface of the bead flaresgradually outwardly and downwardly at 21 to a maximum diameter 20 andthen curves inwardly first gradually at 22 (FIGS. 3 and 10) and thenmore sharply so as to form the shoulder 19 which is thus spaced belowthe maximum diameter 20 a distance b somewhat greater than the totalcompression c (FIG. 10) of the gasket in the final assembly. Below theshoulder the metal of the bead is curved inwardly and horizontally andfinally reversely and upwardly along the outer side of the cup body asindicated at 18 thus completing the bead.

The skirt 17 is an integral continuation of the outer wall of the gasketseat 15 slightly larger and of somewhat lesser cross-sectional curvaturethan the outer surface 21, 22 of the bead 18. Thus, in the finalassembly (FIGS. 6 and 10), the inner surface of the skirt below thegasket is uninterrupted and converges gradually toward the head at 23while curving around the maximum diameter 20 of the bead and then cominginto contact with the latter over a band which includes the shoulder 19.Below the latter, the skirt flares quite gradually away from the bead asindicated at 24 to a bend 25 beyond which the marginal portion of theskirt flares outward to form an internal f-rusto-conical surface 26having a diameter at the edge 27 somewhat greater than the maximumdiameter 20 of the head. The conical surface 26 guides the cover ontothe cup and coacts with the bead with a cam action (see FIGS. 4 and 5)to expand the resilient skirt enough to allow the bend 25 to pass thebead and then spring inwardly beneath the shoulder 19 and bring theskirt surface 24 into contact therewith in .the final position (FIGS. 6and 10) and under sufficient pressure to retain the compression of thegasket 12.

In accordance with the present invention, provision is made for tearingaway the lower portion of the skirt or ribbon-like strip 32 andreleasing the skirt sufiiciently to permit easy removal of the coverwithout substantial deformation of the remaining portion of the skirtwhile at the same time leaving a torn edge 30 which is somewhat smallerthan the maximum diameter 20 of the bead and spaced (see FIGS. 7 and 10)a distance b far enough below the latter to engage the bead 18 and againinterlock effectually the shoulder 19 with a snap-like action or in firmretaining contact so as to hold the gasket against the cup lip 11 whenthe cover is replaced and manually pressed down against the cup lip asshown in FIG. 9. The torn edge 30 is located in this definite positionby scoring the skirt 17 in a conventional operation toform a shallowgroove or score line 31 around the entire circumference of the skirtthus leaving at the bottom of the groove a weakened section about .004of an inch thick over the major portion of its length. Herein, the scoregroove is V-shaped in cross-section and opens outwardly.

Tea-ring the strip 32 away from the cover is effected by grasping anenlargement or tab 33 constituting an extension of the lower edge of theskirt and having an edge 34 defining one side of a split 35 extendinginto the skirt at least to the score line 31 and preferably to a point36 slightly above the latter but short of the gasket 12 as shown in FIG.6. Herein, the split 35 takes the form of a notch of narrow width havingsides which constitute the edges of the tab 33 and a similar second tabwhich may be used alternately in tearing away the lower portion of theskirt to release the cover. The notch is so narrow that, even though itmay extend slightly above the score line 31, the effectiveness of theseal formed by the gasket 12 is maintained, after the initial assemblyof the cover on the cup.

After grasping either one of the two alternately usable tabs 33, theuser pulls the tab outwardly away from the side of the cup thus tearingaway the strip 32 as illustrated in FIG. 1. The tearing is continuedangularly around the cup following the score line 31 until the tearagain reaches the notch 35, the lower portion of the skirt thus beingtorn completely away leaving the raw edge 30 around the entire peripheryof the cover. The skirt remains interlocked as shown in FIG. 7 untilsubstantially all of the strip is torn off. Only a narrow edge portionof the remaining skirt thus remains interlocked with the bead so that,in the absence of a substantial vacuum within the sealed container, thecover may, by tilting thereof under a relatively small lifting force bereleased and removed from the cup as illustrated in FIG. 8 to expose thecontents thereof. Such removal is accompanied by slight expansion of theedge 30 in passing the maximum diameter of the bead, the lower edgeportion of the remaining skirt then contracting owing to the resiliencyof the metal to a diameter smaller than the head as shown in FIG. 8.

In this condition, it will be apparent that the cover may be replaced onthe cup simply by telescoping the skirt down over the bead and applyingenough downward pressure to cause the skirt to expand as the lower edgepasses the maximum bead diameter 20 and then contract inwardly beneaththe shoulder 19 as the gasket 12 comes into contact with the cup lip 11and becomes com-pressed slightly as shown in FIG. 9. The cover is thusheld effectually on the cup, usually under a sealing pressuresubstantially less than in the original assembly but sufficientnevertheless to tightly reclose the cup and offer effective protectionto the contents that may remain in the cup. Such effective rescaling ofthe container is made possible by the novel spacing above describedbetween the spacing of the score line 31 below the maximum diameter 20of the bead 18 the distance somewhat greater than the normal compressionof the gasket 12 in the initial assembly of the cover on the cuptogether with the formation of the skirt of sufficient stiffness andwith a continuous inner surface which is not deformed appreciably eitherin the tearing away of the strip 32 or in the subsequent lifting of thecover to open the cup.

To prevent a prospective customer of the packaged product from havingeasy access to the lower edge of the skirt and forcibly lifting thecover off from the cup, 3. second bead 38 is formed in the wall of thecup 10 and spaced only a short distance below the lower edge of theskirt 17 in the final assembly. Herein, the radial width of 4 the beadis substantially equal to that of the head 18 and the maximum diameteris spaced far enough below the latter to preclude sufficient fingerentry between the beads to enable the skirt to be grasped and enoughlifting force applied to dislodge the cover relative to the cup.

In the packaging of certain products in containers of the abovecharacter, it is desirable to deliver the product in a heated conditioninto the cup. Subsequent cooling of the product is accompanied in someinstances by the development of a substantial vacuum within the sealedcontainer. This vacuum may be of sufficient magnitude to prevent easymanual lifting of the cover off from the cup following removal of thetear strip 32. To overcome this difficulty, the present invention aimsto increase the resistance of the skirt to continued tearing away of thestrip at a selected point around the cup circumference and therebyinduce enough outward bending and deformation of the skirt in an areaabove the score line 31 to substantially pull the remaining margin 42away from the bead 18 as indicated at 43 in FIG. 13 and relieve thecompression of the gasket 12 as illustrated at 44- enough to releasesuch vacuum and permit easy removal of the cover after complete tearingof the strip away from the cover. I have discovered that such increasedresistance may be achieved simply by increasing the thickness of theskirt along the score line 31 at some point or short arcuate length 40(FIG. 1) around the cup circumference. Preferably this are is disposedabout half way around the cup from the tabs 33 so that the increasedresistance will occur after about the same length of the strip has beenremoved irrespective of which of the two tabs 33 is used to initiate thetearing. It has been found that the desired resistance to tearing may beachieved by increasing the thickness of the skirt at score line 31 fromthe normal .004 of an inch (FIG. 10) to about .007 (FIG. 11) when thecover is composed of the alloy above described.

The amount of outward bending and deformation of the torn edge 30 of theskirt over the are 40 will depend somewhat on the angle at which thetear strip is being pulled away from the cup while the thickened length40 is being torn. If the pull on the strip 32 is substantially radial asshown in FIG. 13, the skirt is deformed enough to break the seal under arelatively small vacuum, for example 4.5 inches of mercury. To releasethe seal under higher vacuums, the tear strip may be pulled upwardlyalong an incline or even pulled substantially vertically as shown inFIG. 14. In such a case, the remaining part of the skirt 17 is separateda greater distance away from the cup and may even be lifted slightly tobreak the seal in the course of tearing the strip 32 away from thecover.

When constructed as above described, the cup and cover may be assembledautomatically in a simple and inexpensive machine to achieve the desiredsealing pressure without the necessity of the further rolling ordeforming operations as required in prior containers of the presenttype.

I claim as my invention;

1. A sealed container comprising a cup having a rounded lip and anadjacent peripheral bead whose surface curves outwardly and downwardlyto a plane of maximum diameter and then continues downwardly andinwardly first gradually and then more sharply to form a downwardly andinwardly inclined ledge, a cover of semiresilient material having a topwall and a depending peripheral skirt telescoped over and interlockedwith a snap action with said bead, a gasket of compressible materialextending around the underside of said top wall within and adjacent saidskirt and deformed and compressed against said cup lip, said skirtconverging gradually and continuously toward and around the upperportion of said bead past said plane and then curving inwardly beneathand against said ledge so as to be maintained in contact therewith underthe compression of said gasket at a line of contact spaced below saidplane a distance substantially greater than the compression of thegasket, means providing a score line around said skirt adjacent saidline of contact, a split in said skirt extending transversely thereofinwardly and upwardly from the edge thereof and intersecting said scoreline, and a finger tab integral with said skirt projecting from the edgethereof with one edge of the tab merging with one side of said splitwhereby to permit the lower marginal strip of said skirt to be pulledand torn away from said cover and said head along said score line, saidscore line being substantially smaller in diameter than said maximumbead diameter whereby to leave on the skirt after tearing off said stripan inturned edge adapted, upon replacement of the cover on the cup totelescope down over said bead and contract beneath said ledge with aretaining fit effectually holding the cover on the cup with said gasketin contact with said lip.

2. A sealed container as defined in claim 11 in which the inner end ofsaid notch terminates short of said gasket and including a second fingertab integral with the lower edge of the skirt on the side of the notchopposite said first tab whereby to permit the lower edge of said skirtto be torn away along said score line in either direction around saidcover.

3. A sealed container as defined in claim 1 in which said skirt belowsaid second plane flares outwardly to a diameter greater than saidmaximum diameter and provides an internal surface for guiding the skirtdown over and into snap interengagement with said bead during pressingof the top axially onto said body.

4. A sealed container as defined in claim 3 including a secondperipheral bead of arcuate cross-section formed on said cup immediatelybelow said skirt to substantially close the space between the peripheryof the cup and edge of the skirt.

5. A sealed container having, in combination, a tubular body having alip at its open end and an external peripheral bead extending around theopen end of said body and having an outer surface diverging downwardlyfrom said lip to a maximum diameter in a plane axially spaced below thelip and then converging to form a downwardly and outwardly facingshoulder spaced below said plane, a cover closing the open end of saidbody, a gasket of resilient sealing material on the underside of saidcover and compressed axially between the latter and said lip, aperipheral skirt integral with and depending from the outer edge of saidcover and having an inner surface telescoped with said bead andconverging inwardly and downwardly below said plane and engaging saidshoulder with a tight snap fit to hold said gasket compressed, meansproviding a score line around said skirt adjacent said shoulder, a splitextending transversely of the lower edge portion of said skirt andintersecting said score line, and a finger tab integral with the loweredge of said skirt and merging with one side of said split Whereby topermit the lower marginal strip of said skirt to be pulled and torn awayfrom said cover and said bead along said score line, said skirt at thebottom of said score line being of increased thickness over an arcangularly spaced around the cover from said split whereby to require anincreased pull on said tab in order to tear said strip away from thecover along said arc.

6. A sealed container having, in combination, a tubular body having alip at its open end and an adjacent external peripheral head with anouter surface diverging downwardly from said lip to a maximum diameterin a plane axially spaced below the lip and then converging inwardly toform a downwardly and outwardly facing shoulder spaced below said plane,a cover closing the open end of said body, a gasket of resilient sealingmaterial on the underside of said cover and compressed axially betweenthe latter and said lip, a peripheral skirt integral with and dependingfrom the outer edge of said cover and having an inner surface telescopedwith said head and converging continuously inwardly and downwardlyaround the bead below said plane and contracted against and around saidshoulder so as to hold said gasket compressed, means providing a scoreline around said skirt spaced below said maximum plane and having adiameter substantially smaller than said maximum diameter, a notchextending transversely of the lower edge portion of said skirt andintersecting said score line, and a finger tab integral with the loweredge of said skirt and merging with one side of said notch whereby topermit the lower marginal strip of said skirt to be pulled and torn awayfrom said cover and said bead along said score line, said score linebeing spaced far enough below said maximum diameter to leave the loweredge of the skirt after tearing away said strip disposed below saidmaximum diameter while permitting removal of the cover by expansion ofsaid lower skirt edge, and said cover being composed of resilientmaterial whereby the torn edge of said skirt expands and passes downover the maximum diameter of said bead when the cover is replaced onsaid body and pressed downwardly to reengage said gasket with said lipand then contracts and hooks around said bead shoulder below saidmaximum diameter.

References Cited by the Examiner UNITED STATES PATENTS 1,010,617 12/11Gray 53285 1,106,305 8/14 Hesser 53286 1,765,478 6/30 Aulbach et al.22054 1,921,682 8/33 Loeber 22042 2,430,035 11/47 Thornburgh 220542,977,019 3/61 Henchert 220 FOREIGN PATENTS 3,642 8/ 31 Australia.734,942 5/43 Germany. 641,196 8/50 Great Britain. 674,349 6/52 GreatBritain.

THERON E. CONDON, Primary Examiner.

EARLE J. DRUMMOND, Examiner.

1. A SEALED CONTAINER COMPRISING A CUP HAVING A ROUNDED LIP AND ANADJACENT PERIPHERAL BEAD WHOSE SURFACE CURVES OUTWARDLY AND DOWNWARDLYTO A PLANE OF MAXIMUM DIAMETER AND THEN CONTINUES DOWNWARDLY ANDINWARDLY FIRST GRADUALLY AND THEN MORE SHARPLY TO FORM A DOWNWARDLY ANDINWARDLY INCLINED LEDGE, A COVER OF SEMIRESILIENT MATERIAL HAVING A TOPWALL AND A DEPENDING PERIPHERAL SKIRT TELESCOPED OVER AND INTERLOCKEDWITH A SNAP ACTION WITH SAID BEAD, A GASKET OF COMPRESSIBLE MATERIALEXTENDING AROUND THE UNDERSIDE OF SAID TOP WALL WITHIN AND ADJACENT SAIDSKIRT AND DEFORMED AND COMPRESSED AGAINST SAID CUP LIP, SAID SKIRTCONVERGING GRADUALLY AND CONTINUOUSLY TOWARD AND AROUND THE UPPERPORTION OF SAID BEAD PAST SAID PLANE AND THAN CURVING INWARDLY BENEATHAND AGAINST SAID LEDGE SO AS TOP MAINTAINED IN CONTACT THEREWITH UNDERTHE COMPRESSION OF SAID GASKET AT A LINE OF CONTACT SPACED BELOW SAIDPLANE A DISTANCE SUBSTANTIALLY GREATER THAN THE COMPRESSION OF THEGASKET MEANS PROVIDING A SCORE LINE AROUND SAID SKIRT ADJACENT SAID LINEOF CONTACT, A SPLIT IN SAID SKIRT EXTENDING TRANSVERSELY THEREOFINWARDLY AND UPWARDLY FROM THE EDGE THEREOF AND INTERSECTING SAID SCORELINE, AND A FINGER TAB INTEGRAL WITH SAID SKIRT PROJECTING FROM THE EDGETHEREOF WITH ONE EDGE OF THE TAB MERGING WITH ONE SIDE OF SAID SPLITWHEREBY TO PERMIT THE LOWER MARGINAL STRIP OF SAID SKIRT TO BE PULLEDAND TORN AWAY FROM SAID COVER AND SAID BEAD ALONG SAID SCORE LINE, SAIDSCORE LINE BEING SUBSTANTIALLY SMALLER IN DIAMETER THAN SAID MAXIMUMBEAD DIAMETER WHEREBY TO LEAVE ON THE SKIRT AFTER TEARING OFF SAID STRIPAN INTURNED EDGE ADAPTED, UPON REPLACEMENT OF THE COVER ON THE CUP TOTELESCOPE DOWN OVER SAID BEAD AND CONTACT BENEATH SAID LEDGE WITH ARETAINING GIT EFFECTUALLY HOLDING THE COVER ON THE CUP WITH SAID GASKETIN CONTACT WITH SAID LIP.